1. Field of the Invention
The present invention relates to a light-source holder that is used to hold a light source disposed in an optical pickup, and also relates to an optical pickup having the light-source holder.
2. Description of Related Art
Optical recording media such as compact discs (hereinafter, referred to as CD), digital versatile discs (hereinafter, referred to as DVD) etc. have been widely used. Further, in recent years, optical recording media such as Blu-ray discs (hereinafter, called BD) and the like that can record large-size information have also been put to practical use. To carry out reading and writing of information from and to such an optical recording medium, an optical pickup is used.
In an optical pickup, for example, to carry out reading and writing of information from and to a CD, light having a wavelength of, for example, 780 nm is used. For a DVD, light having a wavelength of, for example, 650 nm is used, and for a BD, light having a wavelength of, for example, 405 nm is used. Accordingly, in some conventional optical pickups, a plurality of light sources which emit light having respective wavelengths different from each other are used.
In an optical pickup, conventionally, a semiconductor laser device is used as a light source that is used to direct light to an optical recoding medium. Such a semiconductor laser device is generally mounted on an optical pickup with held by a holder (e.g, see patent documents 1 to 3). And, if a plurality of semiconductor laser devices are used to carry out reading and writing of information from and to a plurality kinds of optical recording media, the semiconductor laser devices need respective holders.
Laser light emitted from a semiconductor laser device used in an optical pickup is generally linearly polarized light. And, in some optical pickups that comprise a plurality of semiconductor laser devices, polarization directions of laser light (linearly polarized light) emitted from the respective semiconductor laser devices are different from each other. In such a case, because mount directions (mount angles) in which the semiconductor laser devices are mounted on a holder are different from each other, it is necessary to use different-structure holders for the respective semiconductor laser devices. Accordingly, it is necessary to prepare different molds for the different-structure holders and make the holders separately, which causes increase in production cost of the pickups.    [patent document 1] JP No. 3779608    [patent document 2] JP No. 3833934    [patent document 3] JP-A-2004-111507